1. Field of the Invention
The invention relates to a method of producing tarnish- and oxidation-resistant alloys on the basis of copper or silver, small additions of boron and zirconium being added to the melt.
2. Background Art
A method of dispersion hardening of copper, silver or gold as well as of their alloys as matrix material with metal borides as dispersoid, is already known (German Published Patent Application No. 3,522,341); according to this method, the melt on the basis of the matrix metals with stoichiometric additions of boron and boride-forming metals is superheated by 300.degree. to 750.degree. C. to form metal boride in an amount of 1 to 5 volume %, and subsequently subjected to extremely rapid solidification. The necessary superheating of the melt requires high-priced crucible material, and the extremely rapid solidification requires sophisticated powder-metallurgical processes.